Non keep-alive HTTP/1.x requests close the connection immediately wit…

…h compressed responses - fixes #2184

src/main/java/io/vertx/core/http/impl/HttpChunkContentCompressor.java

@@ -31,7 +31,13 @@ public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise)
     if (msg instanceof ByteBuf) {
       // convert ByteBuf to HttpContent to make it work with compression. This is needed as we use the
       // ChunkedWriteHandler to send files when compression is enabled.
-      msg = new DefaultHttpContent((ByteBuf) msg);
+      ByteBuf buff = (ByteBuf) msg;
+      if (buff.isReadable()) {
+        // We only encode non empty buffers, as empty buffers can be used for determining when
+        // the content has been flushed and it confuses the HttpContentCompressor
+        // if we let it go
+        msg = new DefaultHttpContent(buff);
+      }
     }
     super.write(ctx, msg, promise);
   }

src/test/java/io/vertx/test/core/Http1xTest.java

@@ -3722,4 +3722,27 @@ public void testIdleTimeoutWithPartialH2CRequest() throws Exception {
     }));
     await();
   }
+
+  @Test
+  public void testCompressedResponseWithConnectionCloseAndNoCompressionHeader() throws Exception {
+    Buffer expected = Buffer.buffer(TestUtils.randomAlphaString(2048));
+    server.close();
+    server = vertx.createHttpServer(new HttpServerOptions()
+      .setPort(DEFAULT_HTTP_PORT)
+      .setHost(DEFAULT_HTTP_HOST)
+      .setCompressionSupported(true));
+    server.requestHandler(req -> {
+      req.response().end(expected);
+    });
+    startServer();
+    client.get(DEFAULT_HTTP_PORT, DEFAULT_HTTP_HOST, DEFAULT_TEST_URI, resp -> {
+      resp.bodyHandler(buff -> {
+        assertEquals(expected, buff);
+        complete();
+      });
+    }).putHeader("Connection", "close")
+      .exceptionHandler(this::fail)
+      .end();
+    await();
+  }
 }